Parse arrow functions at proper precedence level

src/ast.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_AST_H_
 #define V8_AST_H_
 
 #include "src/assembler.h"
 #include "src/ast-value-factory.h"
 #include "src/bailout-reason.h"
@@ skipping 70 matching lines @@
   V(CallNew)                    \
   V(CallRuntime)                \
   V(UnaryOperation)             \
   V(CountOperation)             \
   V(BinaryOperation)            \
   V(CompareOperation)           \
   V(Spread)                     \
   V(ThisFunction)               \
   V(SuperPropertyReference)     \
   V(SuperCallReference)         \
-  V(CaseClause)
+  V(CaseClause)                 \
+  V(EmptyParentheses)
 
 #define AST_NODE_LIST(V)                        \
   DECLARATION_NODE_LIST(V)                      \
   STATEMENT_NODE_LIST(V)                        \
   EXPRESSION_NODE_LIST(V)
 
 // Forward declarations
 class AstNodeFactory;
 class AstVisitor;
 class Declaration;
@@ skipping 2739 matching lines @@
     DCHECK(this_function_var->raw_name()->IsOneByteEqualTo(".this_function"));
   }
 
  private:
   VariableProxy* this_var_;
   VariableProxy* new_target_var_;
   VariableProxy* this_function_var_;
 };
 
 
+// This class is produced when parsing the () in arrow functions without any
+// arguments and is not actually a valid expression.
+class EmptyParentheses final : public Expression {
+ public:
+  DECLARE_NODE_TYPE(EmptyParentheses)
+
+ private:
+  EmptyParentheses(Zone* zone, int pos) : Expression(zone, pos) {}
+};
+
+
 #undef DECLARE_NODE_TYPE
 
 
 // ----------------------------------------------------------------------------
 // Regular expressions
 
 
 class RegExpVisitor BASE_EMBEDDED {
  public:
   virtual ~RegExpVisitor() { }
@@ skipping 765 matching lines @@
   }
 
   SuperCallReference* NewSuperCallReference(VariableProxy* this_var,
                                             VariableProxy* new_target_var,
                                             VariableProxy* this_function_var,
                                             int pos) {
     return new (zone_) SuperCallReference(zone_, this_var, new_target_var,
                                           this_function_var, pos);
   }
 
+  EmptyParentheses* NewEmptyParentheses(int pos) {
+    return new (zone_) EmptyParentheses(zone_, pos);
+  }
+
  private:
   Zone* zone_;
   AstValueFactory* ast_value_factory_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_AST_H_